Conventionally known temperature sensors for detecting the temperature of exhaust gas from an automobile or the like are described in Patent Documents 1 and 2 mentioned below. These temperature sensors have a thermistor element composed of a thermistor sintered-body and element electrode wires, and a sheath member configured such that sheath core wires are electrically insulatively held in a sheath tube. The element electrode wires and the corresponding sheath core wires are joined together through respective weld zones formed by laser welding.